Most US Veterans Health Administration (VHA) enrollees aged 65 and older were treated for COVID-19 at community hospitals, which reported higher death rates for this group than VHA hospitals in 2020 and 2021, suggests an observational study published yesterday in JAMA Network Open.
Researchers from the Iowa City Veterans Affairs Health Care System in Iowa led the study, which involved evaluating 30-day death and readmission rates among 64,856 hospitalized COVID-19 patients aged 65 and older enrolled in the VHA and Medicare from March 1, 2020, to December 31, 2021.
Participants were hospitalized at 121 VHA and 4,369 community hospitals. A total of 73.7% were admitted to community hospitals (via Medicare [56.1%] or via the VHA's Care in the Community [CITC] program [17.7%]), and 26.3% were admitted to VHA hospitals. The average age was 77.6 years, and 98.0% were men.
The study authors noted that many veterans have poor geographic access to VHA hospitals, with 41% of enrollees aged 65 years or older living more than 60 minutes from the nearest VHA center. "In contrast, nearly all VHA enrollees aged 65 years or older (98%) live within a 60-minute drive to 1 of the approximately 4400 community hospitals with acute care units in the US," they wrote.
Readmission more common in VHA centers
Admission to community hospitals was tied to a higher unadjusted and risk-adjusted 30-day death rate than admission to VHA hospitals (crude mortality, 12,951 of 47,821 [27.1%] vs 3,021 of 17,035 [17.7%]; risk-adjusted odds ratio, 1.37). Readmission within 30 days was less common after admission to community than VHA hospitals (4,898 of 38,576 [12.7%] vs 2,006 of 14,357 [14.0%]; risk-adjusted hazard ratio, 0.89).
The median distance from patients to the nearest VHA hospital was 113.6 kilometers (km), equivalent to 78.6 miles, among enrollees admitted to community hospitals, compared with 36.2 km (22.5 miles) among those admitted to VHA hospitals. Admissions through the VHA's CITC program became more common over time; 27.4% of these admissions occurred in the last 4 months of the study, compared with 17.7% of Medicare admissions.
Community hospitals were less likely than their VHA counterparts to be located in an urban area (53.8% vs 89.3%) and had fewer total beds (average, 170.9 vs 253.6). Relative to VHA hospitals, community facilities were less likely to be members of the Council of Teaching Hospitals (5.4% vs 21.5%) or to be academically affiliated (35.8% vs 85.1%).
About a quarter of community hospitals caring for VHA enrollees with COVID-19 (24.7%) were in rural areas and designated as Critical Access Hospitals. A total of 62.6% of community hospitals admitted VHA enrollees via both Medicare and the VHA's CITC program.
A multivariable logistic regression model showed that admission to a VHA rather than a community hospital was linked to younger patient age, shorter distance to a VHA hospital, residence in a high social-vulnerability census tract, and more underlying medical conditions.
"Since the beginning of the COVID-19 pandemic, the VHA health care system has worked to rapidly implement advances in care according to the latest treatment guidelines, including use of antiviral medications, corticosteroids, and other anti-inflammatory medications for people with severe COVID-19," the researchers wrote.
Future studies should assess whether higher readmission rates in VHA hospitals reflect an undesired outcome or a necessary aspect of efforts to improve access to primary care during care transitions.
"It is important for the VHA to understand the role of rural community hospitals in acute care for rural VHA enrollees—both during surges in demand for care during pandemics and overall—so that the VHA can support and collaborate with these hospitals to maintain access to care for rural veterans," they added.
The slightly higher readmission rates at VHA hospitals may have partly resulted from VHA programs to track veterans and manage care transitions after hospital release, the authors said. "Future studies should assess whether higher readmission rates in VHA hospitals reflect an undesired outcome or a necessary aspect of efforts to improve access to primary care during care transitions," they wrote.
Some caveats for interpretation
In a related commentary, Michael Klompas, MD, MPH, of Harvard Medical School, and Barbara Jones, MD, of the University of Utah in Salt Lake City, said several factors may have skewed the study results, such as including patients who were transferred between VHA and community hospitals, assigning them to their final site of care for analysis. This, they said, could have reduced the death rate in VHA hospitals and increased it in community hospitals.
"Indications for transfer from VHA hospitals to non-VHA hospitals and the reverse are different," they wrote. "Many VHA hospitals are smaller than their community counterparts and may have needed to transfer patients with more severe disease to non-VHA hospitals (eg, those requiring extracorporeal membrane oxygenation). Conversely, veterans initially admitted to non-VHA hospitals are typically transferred to VHA hospitals only once they are stabilized and recovering."
The difference in death rates may also have been influenced by COVID-19 testing protocols, with most VHA hospitals testing all patients at admission, and wide variation in the practice at community hospitals.
"This allows for the possibility of ascertainment bias, where VHA hospitals were more likely to diagnose COVID-19 in patients with milder illness (and later in the pandemic, possibly even misdiagnose COVID-19 in patients with residual viral debris alone from remote prior infection)," Klompas and Jones wrote. "This too would lead to lower perceived COVID-19 mortality rates in VHA vs community hospitals."
Last, the researchers didn't offer supporting data to explain the difference in death rates between the two types of hospitals, they said. "Documenting meaningful differences in these parameters would not only support the validity of the observed mortality difference between VHA vs community hospitals but would also help identify which VHA practices should be emulated by other institutions," they wrote.